JP4760933B2 - Conveying device, double feed sign detection device, and double feed sign detection program - Google Patents

Description

  The present invention relates to a conveyance device, a double feed sign detection device, and a double feed sign detection program.

  There is a paper transport device that transports stacked paper one by one in the transport direction (see, for example, Patent Documents 1 to 4).

  In Patent Document 1, the presence or absence of a paper feed is determined using a paper detection sensor, and when it is determined that a paper feed has occurred, the transport roller is stopped to stop the transport of the following paper. And a paper transport device for preventing the paper from being fed.

  Patent Document 2 discloses a paper feed roller that feeds paper placed on a tray one by one, a paper detection unit that outputs a detection signal when the paper fed by the feed roller reaches a predetermined position, and A sheet feeding device that detects the feeding performance of the sheet feeding roller based on the length of time from when the sheet feeding roller starts feeding the sheet to when the sheet detecting means outputs the detection signal. Are listed.

  In Patent Document 3, the actual sheet conveyance time t detected by the timing sensor installed in the sheet conveyance path is compared with the deterioration determination setting time T ′ a predetermined number of times (N), and t ≧ T There is described an image forming apparatus that counts the number of times “n” (n) and displays warning information when the number of times (n) exceeds a preset number of times of determination (m). That is, Japanese Patent Application Laid-Open No. H10-228561 describes that when the paper conveyance speed is slowed down due to deterioration such as wear of a paper feed roller, this is detected and warning information is displayed.

  Patent Document 4 discloses a pickup roll that picks up paper from a paper feed tray, a pair of paper feed rolls that conveys and picks up paper from the pickup roll, and a first sensor that detects paper from the pair of paper feed rolls. In the transport apparatus, the displacement information acquisition unit is provided at a position facing the paper in the paper feed tray, and the rear end of the paper is detected by the first sensor from the time when the rear end of the paper passes the displacement information acquisition unit. Time, that is, the time for the trailing edge of the sheet to pass between the displacement information acquisition unit and the first sensor is determined as the transport time, and the failure of the pick-up roll and the paper feed roll pair is determined based on the distribution of the transport time. It is described.

JP 2006-82889 A Japanese Utility Model Publication No. 3-56734 JP 2000-307786 A JP 2005-206307 A

  By the way, in the case where the loaded transported objects are sent one by one in the transport direction, if it is possible to detect in advance a state in which the transported objects are likely to be double-fed, for example, replacement of the transported objects or the transport device It is possible to deal with parts replacement, which is significant.

  The present invention relates to a transport device capable of detecting a sign of occurrence of double feed of a transported body, a multi-feed sign detecting device, An object is to provide a transmission sign detection program.

The transport device according to the present invention is a delivery means for separating the transported bodies stacked on the stacking section one by one and sending them in the transporting direction, and is taken out from the stacking section together with the transported target body. A feeding unit including a separating unit that applies a force in a direction opposite to a conveying direction to the conveyed object at a separating unit, and separates the taken-out conveyed object from the conveyed object to be conveyed; and the stacking unit A protrusion amount detecting means for detecting a protrusion amount of the transported body loaded in the transport direction from the stacking portion , deterioration of the separation means based on the detection result of the protrusion amount , and deterioration of the separation means and multifeed sign detection means for determining a double feed sign of occurrence of the conveyance object not caused, were perforated in the multifeed sign detection means, with respect to the protrusion amount the protrusion amount detecting means detects said load As seen from the department Corresponding to a first threshold value corresponding to a protruding amount up to a predetermined first position exceeding the portion and a protruding amount up to a predetermined second position before the separating portion as viewed from the stacking portion And when the occurrence frequency of the amount of protrusion exceeding the first threshold is higher than a predetermined reference, it is determined that the separation unit has deteriorated, and the second threshold If the occurrence frequency of the protrusion amount exceeding the predetermined threshold is higher than a predetermined criterion and the occurrence frequency of the protrusion amount exceeding the first threshold is lower than the predetermined criterion, it does not result from deterioration of the separation means. It is determined that there is a sign of occurrence of double feeding .

  Also, in one aspect of the present invention, there is provided a type discriminating unit that discriminates the type of the transported object loaded on the stacking unit, and the double feed predictor detecting unit is provided with a determination result of the type of the transported object. On the basis of the type of the transported body, the sign is detected or the deterioration is determined based on the detection result of the amount of protrusion in the type.

The double feed sign detection device according to the present invention is a sending means for separating the transported bodies loaded in the stacking section one by one and sending them in the transporting direction, and is accompanied with the transported target body from the stacking section. A feeding unit including a separating unit that applies a force in a direction opposite to a conveying direction to the ejected object to be transported by a separation unit, and separates the transported object to be transported from the object to be transported; A multi-feed sign detection device connected to a transport device provided, wherein the transported bodies loaded on the stacking portion are stacked on the stacking portion when the transported units are sent one by one in the transport direction by the sending means. A protruding amount detecting means for detecting a protruding amount of the transferred object in the conveying direction from the stacking portion , and a separation of the separating means based on a detection result of the protruding amount, and a transferred object not caused by the deterioration of the separating means Body weight Sign of the occurrence, possess a multifeed sign detection means for determining, the a, the multifeed sign detection means, with respect to the protrusion amount the protrusion amount detecting means detects, exceeds the separating portion when viewed from the stacking unit A first threshold value corresponding to a protrusion amount up to a predetermined first position, and a second threshold value corresponding to a protrusion amount up to a predetermined second position before the separation portion as viewed from the stacking portion. And when the occurrence frequency of the amount of protrusion exceeding the first threshold is higher than a predetermined reference, it is determined that the separation means has deteriorated, and the second threshold is set to When the occurrence frequency of the overhanging amount is higher than a predetermined criterion and the occurrence frequency of the overhanging amount exceeding the first threshold is lower than a predetermined criterion, the double feed not caused by the deterioration of the separating means And judging that there is a sign of occurrence.

The multifeed sign detection program according to the present invention is a sending means for separating the transported objects loaded on the stacking unit one by one and sending them in the transporting direction, and is accompanied by the transported target object from the stacking unit. A feeding unit including a separating unit that applies a force in a direction opposite to a conveying direction to the ejected object to be transported by a separation unit, and separates the transported object to be transported from the object to be transported; In the case where the objects to be transported loaded in the stacking unit are sent one by one in the transporting direction to the computer connected to the transporting device provided in the transporting direction, the stacking of the objects to be transported stacked in the stacking unit a protrusion amount detecting step of detecting the amount of protrusion of the transport direction from the part, based on the protrusion amount of the detection result, the deterioration of the separating means, and heavy no feeding of the conveyance object not due to degradation of the separating means A sign detection procedure for determining raw sign, and allowed to run, the in the sign detection procedure, with respect to the protrusion amount to be detected by the protrusion amount detection procedure, predetermined exceeds the separating portion when viewed from the stacking unit A first threshold value corresponding to an amount of protrusion up to a position 1 and a second threshold value corresponding to an amount of protrusion up to a predetermined second position before the separation unit as viewed from the stacking unit, And when the occurrence frequency of the protrusion amount exceeding the first threshold is higher than a predetermined reference, it is determined that the separation means has deteriorated, and the occurrence of the protrusion amount exceeding the second threshold is generated. If the frequency of occurrence of the protrusion amount that is higher than a predetermined criterion and exceeds the first threshold is lower than a predetermined criterion, the occurrence of double feeding that does not result from the deterioration of the separating means Wherein the determining that there is a sign.

  According to the first aspect of the present invention, it is possible to provide a transport device that detects a sign of occurrence of double feed of a transported body.

  According to the second aspect of the present invention, it is possible to provide a transport device that detects a phenomenon in which the amount of protrusion exceeding the threshold frequently occurs as a sign of occurrence of double feed.

  According to the third aspect of the present invention, it is possible to provide a transport device that detects the deterioration of the separating means that separates the transported transported body from the transported transport target.

  According to invention of Claim 4, the conveying apparatus which determines appropriately deterioration of a separation means can be provided.

  According to the fifth aspect of the present invention, it is possible to provide a transport apparatus that appropriately detects the sign of occurrence of double feed or determines the deterioration of the separation means for each type of transport target.

  According to the sixth aspect of the present invention, it is possible to provide a double feed sign detection device that detects a sign of occurrence of double feed of a transported body.

  According to the seventh aspect of the present invention, it is possible to provide a double feed sign detection program for detecting a sign of occurrence of double feed of a conveyed object.

1 is a schematic diagram illustrating an example of a configuration of an image forming apparatus including a conveyance device according to an embodiment. FIG. 6 is a diagram illustrating a state in which sheets stacked on a stacking unit protrude to the front of a separation unit. FIG. 6 is a diagram illustrating a state in which sheets stacked on a stacking unit protrude beyond a separating unit. It is a block diagram which shows an example of a function structure of the double feed sign detection apparatus in 1st Embodiment. It is a figure which shows an example of the generation pattern of an abnormal value. It is a figure which shows an example of the generation pattern of an abnormal value. It is a flowchart which shows an example of operation | movement of the double feed sign detection apparatus in 1st Embodiment. It is a block diagram which shows an example of a function structure of the double feed sign detection apparatus in 2nd Embodiment. It is a flowchart which shows an example of operation | movement of the double feed sign detection apparatus in 2nd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a schematic diagram illustrating an example of a configuration of an image forming apparatus 100 including a conveyance device 20 according to an embodiment. The image forming apparatus 100 is an apparatus for forming an image on a recording medium P such as paper (hereinafter referred to as “paper”), such as a copying machine, a printer, and a facsimile machine. Here, the electrophotographic printing is performed by an electrophotographic method. Device. However, the image forming apparatus 100 may use another printing method such as an inkjet method. In FIG. 1, the image forming apparatus 100 includes an image forming unit 10 and a conveying device 20.

  The image forming unit 10 forms an image on a sheet according to an electrophotographic process. Since the image forming unit 10 is widely known, illustration and detailed description of its specific configuration are omitted. In brief, the image forming unit 10 typically includes a photoconductor, a charging device disposed around the photoconductor, an exposure device, a developing device, a transfer device, a cleaning device, and a fixing device. Then, an electrostatic latent image is formed on the photosensitive member by the charging device and the exposure device, the electrostatic latent image is visualized (toner image) by the developing device, and the toner image on the photosensitive member is transferred onto the paper by the transfer device. Then, the transferred toner image is fixed on the paper by a fixing device.

  The transport device 20 includes a delivery mechanism 21 that feeds the transported bodies (here, sheets) stacked on the stacking unit 1 one by one in the transport direction (in the direction indicated by the arrow X in the figure). In the example of FIG. 1, the stacking unit 1 is a paper feed tray that stores paper. 1 shows one stacking unit 1, a plurality of stacking units 1 may be provided. Further, the stacking unit 1 is not limited to the paper feed tray, and may be, for example, a manual feed tray on which paper is placed.

  Specifically, the delivery mechanism 21 applies a force in the conveyance direction to a sheet to be conveyed (for example, the uppermost sheet) and conveys the sheet to be conveyed in the conveyance direction from the stacking unit 1. A separation unit that applies a force in a direction opposite to the conveyance direction to the sheet taken out together with the target sheet, and separates the taken out sheet from the conveyance target sheet.

  In one embodiment, as shown in FIG. 1, the delivery mechanism 21 includes a pickup roll 22 disposed facing the uppermost sheet among the sheets stacked on the stacking unit 1, and the pickup roll 22. A feed roll 23 provided on the downstream side in the transport direction, and a separation roll (retard roll) 24 that is in pressure contact with the feed roll 23 and forms a separation part (nip part) N between the feed roll 23 and including.

  The pickup roll 22 is driven to rotate in a state of being in contact with the uppermost sheet, thereby feeding the uppermost sheet in the transport direction. The pickup roll 22 may be driven by an actuator such as a solenoid so as to be switched between a state in contact with the uppermost sheet and a state in which the pickup roll 22 does not contact.

  The feeding roll 23 is rotationally driven in the same rotational direction as the pickup roll 22, that is, a direction in which the paper is further conveyed forward, and conveys the paper fed out by the pickup roll 22 in the conveyance direction.

  When the next sheet is taken out together with the uppermost sheet from the stacking unit 1 by the pickup roll 22, the separation roll 24 applies a force in the direction opposite to the transport direction to the taken-out sheet at the separation unit N. , And plays the role of separating the taken-out paper from the uppermost paper.

  Specifically, rotational torque in the direction opposite to the paper transport direction is applied to the separation roll 24 via a torque limiter. When there is no sheet in the separation unit N and when only one sheet is fed into the separation unit N, a rotational torque exceeding the limit value of the torque limiter acts on the separation roll 24, and the separation roll 24 The feed roll 23 rotates in the transport direction. On the other hand, when two or more sheets are fed into the separation unit N, the separation roll 24 rotates in the direction opposite to the sheet conveyance direction, and the sheet in contact with the separation roll 24 is moved toward the stacking unit 1. And push back. As a result, the uppermost sheet in contact with the feeding roll 23 is conveyed in the conveying direction by the rotation of the feeding roll 23, while the sheet taken along with the uppermost sheet and entering the separation unit N is The separation roll 24 is pushed back in the direction opposite to the conveyance direction.

  The specific configuration of the delivery mechanism 21 is not limited to the above. For example, a separation pad may be used instead of the separation roll 24, and a separation member such as the separation roll 24 is pressed against the pickup roll 22. Also good.

  In the example of FIG. 1, the transport device 20 further transports the paper fed by the feed mechanism 21 to the transfer portion, transports the paper after transfer to the fixing unit, and discharges the paper after fixing to the discharge tray 3. It has a transport mechanism. Specifically, the transport device 20 includes one or more transport rolls 25 provided in the transport path for transporting the paper from the delivery mechanism 21 along the transport path. The one or more transport rolls 25 may include, for example, a registration roll for adjusting the position of the paper. Further, the transport device 20 includes one or more paper sensors 26 for paper transport control that are provided in the transport path and detect the presence or absence of paper.

  Further, the transport device 20 includes a transport control device 27 that controls the transport of paper. Specifically, the transport control device 27 controls the transport of the paper by controlling the operation of the feeding mechanism 21 and the transport roll 25 based on the output from the paper sensor 26 and the like.

  In the transport device 20 having the above-described configuration, when the separation performance of the separation unit is deteriorated (for example, when the friction coefficient of the separation roll 24 is reduced), or when the adsorption force or frictional resistance between the sheets is large, the feeding mechanism 21. May cause a phenomenon in which a plurality of sheets are overlapped and fed out at a time (that is, double feeding). When the double feed occurs, for example, the double feed is detected by the carry control device 27, and the paper carrying operation is stopped.

  In the stage before the occurrence of the multifeed, as shown in FIGS. 2 and 3, a phenomenon in which the next sheet after the fed sheet protrudes beyond the end surface of the stacking unit 1 in the conveyance direction is observed. FIG. 2 shows a state in which the paper loaded on the stacking unit 1 protrudes to the front of the separation unit N. In FIG. 3, the paper loaded on the stacking unit 1 passes through the separation unit N. It is shown that it protrudes beyond.

  In the present embodiment, the transport device 20 includes a multifeed sign detection device 30 that detects a sign of occurrence of double feed of paper from the viewpoint of preventing the occurrence of the stop of the transport operation due to the multifeed.

  In one aspect, the double feed sign detection device 30 is realized by cooperation of hardware resources and software. Specifically, various functions of the double feed sign detection device 30 are such that a program recorded on a recording medium such as a ROM (Read Only Memory) is read out to a main storage device (main memory) and a central processing unit (CPU: This is implemented by being executed by the Central Processing Unit. The program can be provided by being recorded on a computer-readable recording medium such as a CD-ROM, or can be provided by communication as a data signal. However, the double feed sign detection device 30 may be realized only by hardware. Further, the double feed sign detection device 30 may be physically realized by one device or may be realized by a plurality of devices. The implementation mode of the transfer control device 27 is the same as that of the double feed sign detection device 30. The conveyance control device 27 and the double feed sign detection device 30 may be realized by a single device, and may be included in a control device that controls the entire image forming apparatus 100, for example.

  FIG. 4 is a block diagram illustrating an example of a functional configuration of the double feed sign detection device 30. In FIG. 4, the double feed sign detection device 30 includes a protrusion amount detection unit 31, a double feed sign detection unit 32, and a process execution unit 33.

  The protrusion amount detection unit 31 detects an amount of protrusion of the sheets stacked on the stacking unit 1 in the transport direction from the stacking unit 1. For example, in FIGS. 2 and 3, the amount of protrusion is represented by a length L. The protrusion amount detection unit 31 may substantially detect the protrusion amount, and may acquire information indicating the protrusion amount.

  In one embodiment, from the viewpoint of detecting the amount of protrusion with a simple configuration, the amount of protrusion detection unit 31 indicates the amount of protrusion from the start of sheet feeding to the arrival of the sheet at a specific position. Detect as. Specifically, as shown in FIGS. 2 and 3, a sheet sensor 34 that detects the presence or absence of a sheet is disposed at a specific position P <b> 1 on the downstream side in the transport direction, and the protrusion amount detection unit 31 performs sheet feeding. The time from the start until the paper sensor 34 detects the arrival of the paper at the paper sensor 34 is measured as the conveyance time. Note that the paper sensor 26 for transport control may be used as the paper sensor 34.

  However, the protrusion amount detection unit 31 may detect the protrusion amount in a mode other than the above. For example, with reference to FIGS. 2 and 3, the protrusion amount detection unit 31 may detect the protrusion amount L itself using various sensors, or the sheet conveyance distance L <b> 1 up to a specific position P <b> 1. May be detected. Further, the protrusion amount detection unit 31 may detect the positional deviation amount L2 of the trailing edge of the sheet by using the technique described in Patent Document 4.

  In the example of FIG. 4, the protrusion amount detection unit 31 includes a paper feed start detection unit 31a, a paper arrival detection unit 31b, a conveyance time measurement unit 31c, a reference time storage unit 31d, a difference calculation unit 31e, and a time series data storage unit 31f. including.

  The paper feed start detection unit 31 a detects the paper feed start by the feed mechanism 21. Specifically, the paper feed start detection unit 31 a receives an activation signal for the delivery mechanism 21 from the conveyance control device 27. Examples of the activation signal include a drive start signal of a motor that rotationally drives the pickup roll 22, and an ON signal of a solenoid for bringing the pickup roll 22 into contact with the uppermost sheet.

  The paper arrival detection unit 31b detects the arrival of the fed paper at a specific position. Specifically, as shown in FIGS. 2 and 3, a sheet sensor 34 that detects the presence or absence of a sheet is disposed at a position P1 on the downstream side in the transport direction of the separation unit N, and the sheet arrival detection unit 31b includes: A detection signal from the paper sensor 34 is received.

  The transport time measurement unit 31c measures the transport time from the start of paper feed to the arrival of the paper at a specific position based on the detection results of the paper feed start detection unit 31a and the paper arrival detection unit 31b. Specifically, when the activation signal is received by the paper feed start detection unit 31a, the conveyance time measurement unit 31c starts measuring the elapsed time by the timer, and when the detection signal is received by the paper arrival detection unit 31b. The elapsed time from the timer is stopped, and the elapsed time from the reception of the activation signal to the reception of the detection signal is measured as the conveyance time.

  The reference time storage unit 31d stores in advance as a reference time the time from the start of feeding to the arrival of the paper at a specific position. The reference time is a time set in advance by experiment or calculation, for example, and is an ideal transport time, for example.

  The difference calculation unit 31e calculates a difference between the reference time stored in the reference time storage unit 31d and the transport time measured by the transport time measurement unit 31c. This difference is the time corresponding to the amount of protrusion (length L in FIGS. 2 and 3) of the paper stacked on the stacking unit 1, and can be said to be data indicating the amount of protrusion. For example, if the sheet does not protrude, the difference is substantially zero, and the difference increases as the amount of protruding sheet increases.

  The time series data storage unit 31f sequentially stores the difference that is the calculation result of the difference calculation unit 31e, and stores the time series data of the difference.

  The double feed sign detection unit 32 detects a sign of occurrence of double paper feed based on the detection result of the protrusion amount detection unit 31. Specifically, the double feed sign detection unit 32 determines the presence or absence of a sign of occurrence of double feed based on the detection results of the protrusion amount for a plurality of times. For example, the double feed sign detection unit 32 determines whether or not there is a sign of occurrence of double feed based on the time series data of the difference stored in the time series data storage unit 31f.

  In one aspect, the double feed sign detection unit 32 determines the occurrence frequency of the amount of protrusion exceeding the predetermined threshold (hereinafter referred to as “abnormal value”) based on the detection result of the amount of protrusion based on a predetermined reference. When it is high, it is determined that there is a sign of occurrence of double feeding. Here, the threshold value will be described with reference to FIGS. 2 and 3. For example, the protrusion amount L11 to a specific position P11 before the separation unit N, the protrusion amount L12 to the position P12 of the separation unit N, and the separation A protruding amount L13 to a specific position P13 in front of the sheet sensor 34 beyond the portion N is set.

  In another aspect, the double feed sign detection unit 32 determines the occurrence frequency of the abnormal value and the occurrence frequency of the abnormal value group based on the detection result of the protrusion amount, and the occurrence frequency of the abnormal value is determined in advance. If it is higher than the reference and the occurrence frequency of the abnormal value group is higher than a predetermined reference, it is determined that there is a sign of occurrence of double feed.

  The above abnormal value group will be described. According to the first definition, a series of abnormal values when an abnormal value occurs continuously M times or more is taken as one abnormal value group. The M is a predetermined integer of 1 or more. For example, when an abnormal value occurs in the pattern shown in FIG. 5, when M = 2, seven abnormal value groups G1 to G7 are generated. According to the second definition, N consecutive abnormal values are set as one abnormal value group. N is an integer of 2 or more determined in advance. For example, when an abnormal value occurs in the pattern shown in FIG. 6, when N = 2, 11 abnormal value groups H1 to H11 are generated.

  When the paper loaded on the stacking unit 1 protrudes beyond the separation unit N, it is possible that the separation unit has deteriorated. Therefore, in one aspect, the double feed predictor detection unit 32 uses the separation means (for example, the separation roll 24) when the paper stacked on the stacking unit 1 protrudes beyond the separation unit N based on the detection result of the protrusion amount. Is determined to be deteriorated.

  In this aspect, the double feed sign detection unit 32 may determine that the separation unit has deteriorated when the amount of protrusion exceeding the separation unit N is detected once, but in this case, it happens to happen. Even when it exceeds the separation part N, it may be judged that the separation means is deteriorated, such as a case where it is not correctly judged.

  Therefore, in one aspect, the double feed sign detector 32 separates the separation unit N or the separation means when the occurrence frequency of the amount of protrusion exceeding the specific position downstream of the separation unit N in the transport direction is higher than a predetermined reference. Is determined to be deteriorated. For example, with reference to FIGS. 2 and 3, the double feed predictor detection unit 32 calculates the amount of protrusion L12 up to the position P12 of the separation unit N or the amount of protrusion L13 up to the specific position P13 downstream from the separation unit N in the transport direction. When the occurrence frequency of the amount of protrusion (abnormal value) exceeding the threshold is higher than a predetermined standard as the threshold, it is determined that the separation unit has deteriorated.

  A phenomenon indicating deterioration of the separating means (for example, a phenomenon in which the paper frequently exceeds the separating portion) is also a predictive phenomenon of occurrence of double feeding. Therefore, the double feed sign detection unit 32 may substantially detect a sign of occurrence of double feed by determining whether or not the separation means has deteriorated.

  On the other hand, the sign phenomenon of occurrence of double feed is not only a phenomenon indicating the deterioration of the separating means (for example, a phenomenon in which the paper frequently exceeds the separating portion), but an excessive amount of protrusion occurs frequently even if it does not exceed the separating portion. The phenomenon can also be regarded as a precursor to the occurrence of double feed. Therefore, the double feed sign detection unit 32 may perform both detection of a sign of occurrence of double feed and determination of deterioration of the separation unit. For example, if the occurrence frequency of the amount of protrusion exceeding the threshold value L11 is higher than the reference and the occurrence frequency of the amount of protrusion exceeding the threshold value L13 is equal to or less than the reference, the double feed predictor detection unit 32 may indicate the occurrence of the double feed. If it is determined that there is a protrusion amount exceeding the threshold L13 and the occurrence frequency is higher than the reference, it is determined that the separation unit has deteriorated.

  The double feed sign detection unit 32 outputs the detection result of the double feed sign and the result of the deterioration determination of the separating means. In the example of FIG. 4, the double feed sign detection unit 32 outputs the sign detection result and the deterioration determination result to the process execution unit 33. However, the double feed sign detection unit 32 may notify the user and the conveyance control device 27 of the sign detection result and the deterioration determination result.

The process execution unit 33 executes a predetermined process corresponding to the case (for example, a process for preventing the occurrence of double feed) when the double feed sign detection unit 32 detects a sign of occurrence of double feed. To do. Examples of the process include the following processes (a1) to (a3).
(A1) Notify the user of warning information regarding a sign of occurrence of double feeding. For example, warning information is displayed on the display screen of the user interface. The warning information includes, for example, a message that prompts the user to check and replace the sheet, a message that indicates that the delivery mechanism 21 needs to be maintained, and a message that prompts replacement or cleaning of the parts of the delivery mechanism 21 (for example, the separation roll 24). Etc.
(A2) Control is performed to pull back the sheet protruding from the stacking unit 1 to the stacking unit 1 side. For example, the pickup roll 22 is rotated in the direction opposite to the conveyance direction, and the sheets stacked on the stacking unit 1 are moved in the direction opposite to the conveyance direction.
(A3) Control to increase the applied pressure between the feed roll 23 and the separation roll 24 is performed.

  Note that the process execution unit 33 may notify the transport control device 27 of a warning regarding the sign of occurrence of double feed, and cause the transport control device 27 to execute the processes (a2) and (a3).

  In addition, when the deterioration of the separating unit is detected by the double feed sign detection unit 32, the process execution unit 33 executes a predetermined process corresponding to the case. For example, the process execution unit 33 notifies the user of warning information regarding the deterioration of the separation unit. Examples of the warning information include a message indicating that the delivery mechanism 21 needs to be maintained, and a message for prompting replacement or cleaning of the parts of the delivery mechanism 21 (for example, the separation roll 24). The process execution unit 33 may execute the processes (a2) and (a3).

  FIG. 7 is a flowchart showing an example of the operation of the double feed sign detection device 30. Hereinafter, an example of the operation of the double feed sign detection device 30 will be described with reference to FIG.

  In step S <b> 11, the double feed sign detection device 30 detects the start of driving of the motor that drives the pickup roll 22. The double feed sign detection device 30 is in a standby state until the start of driving is detected.

  In step S <b> 12, the double feed sign detection device 30 detects the arrival of the paper at the paper sensor 34 by the paper sensor 34.

  In step S13, the double feed sign detection device 30 performs the conveyance time from the start of paper feed to the paper sensor 34 based on the paper feed start timing detected in step S11 and the paper arrival timing detected in step S12. Is calculated.

  In step S14, the double feed sign detection device 30 calculates the difference between the reference time stored in advance and the transport time calculated in step S13.

  In step S15, the double feed sign detection device 30 accumulates the difference calculated in step 14. Specifically, the double feed sign detection device 30 updates the time-series data of the difference with the calculated difference. Here, the number of data of the time series data is fixed to a fixed number of times, and the double feed sign detection device 30 deletes the oldest difference data when adding new difference data to the time series data. Therefore, the time-series data holds data up to the number of times going back a certain number of times from the latest data.

  In step S16, the double feed sign detection device 30 evaluates the distribution (occurrence frequency) of the time series data of the differences updated in step S15. Specifically, the double feed sign detection device 30 identifies a difference value (abnormal value) exceeding a predetermined threshold among the difference values included in the time series data, and the abnormal value has occurred within a certain number of times. The number of times and the number of times the abnormal value group has occurred within a certain number of times are calculated.

  In step S17, the double feed sign detection device 30 determines whether or not the number of occurrences of the abnormal value calculated in step S16 exceeds a predetermined reference number, and if not (S17). : NO), the process returns to step S11, and if it exceeds (S17: YES), the process proceeds to step S18.

  In step S18, the double feed sign detection device 30 determines whether or not the number of occurrences of the abnormal value group calculated in step S16 exceeds a predetermined reference number. (S18: NO), the process returns to step S11, and if it exceeds (S18: YES), the process proceeds to step S19.

  In step S <b> 19, the double feed sign detection device 30 notifies the user and the transport control device 27 of a warning indicating that a sign of occurrence of double feed has been detected.

[Second Embodiment]
By the way, the attractive force and frictional resistance between sheets differ depending on the type of sheet, and therefore the amount of protrusion of the sheet varies depending on the type of sheet. Specifically, the amount of protrusion tends to increase as the basis weight of the paper increases for paper types and the surface gloss increases for paper quality. Therefore, for example, when a different type of paper is set in the stacking unit 1, the paper type is determined based on the detection result of the amount of protrusion on the current paper and the detection result of the amount of protrusion on the previous paper. It is conceivable that an appropriate result cannot be obtained if the sign detection or the deterioration determination is performed without distinction.

  In the second embodiment, the double feed sign detection device 40 performs sign detection and deterioration determination for each type of transported object. Hereinafter, the double feed sign detection device 40 will be described, but the description common to the first embodiment will be omitted or simplified.

  FIG. 8 is a block diagram illustrating an example of a functional configuration of the double feed sign detection device 40. In FIG. 8, the double feed sign detection device 40 includes a type determination unit 44 in addition to a protruding amount detection unit 41, a double feed sign detection unit 42, and a process execution unit 43.

  The type discriminating unit 44 discriminates the type of the transported body loaded on the stacking unit 1. Here, the transported body is a sheet, and the type determination unit 44 determines the type of sheet (that is, the sheet type) such as the material of the sheet (that is, the paper quality) and the basis weight of the sheet. The type discriminating unit 44 may discriminate the paper type based on, for example, paper type information set by the user (for example, paper type setting information for each paper feed tray), or paper by a paper type sensor (not shown). The paper type may be determined based on the detection result of the gloss characteristics and transmission characteristics.

  The protrusion amount detection unit 41 is the same as the protrusion amount detection unit 31 according to the first embodiment. However, in one aspect, the protrusion amount detection unit 41 stores the detection result of the protrusion amount for each paper type based on the determination result of the type determination unit 44.

  In the example of FIG. 8, the protrusion amount detection unit 41 includes a paper feed start detection unit 41a, a paper arrival detection unit 41b, a conveyance time measurement unit 41c, a reference time storage unit 41d, a difference calculation unit 41e, and a time series data storage unit 41f. including.

  The paper feed start detection unit 41a, the paper arrival detection unit 41b, the transport time measurement unit 41c, the reference time storage unit 41d, and the difference calculation unit 41e are the same as those in the first embodiment. However, the reference time storage unit 41d may store the reference time set for each paper type in consideration of the difference in the conveyance speed and the conveyance time depending on the paper type. The difference calculation unit 41e may calculate the difference using a reference time corresponding to the paper type to be transported based on the determination result of the type determination unit 44.

  The time series data storage unit 41f sequentially stores the difference, which is the calculation result of the difference calculation unit 41e, for each paper type based on the determination result of the type determination unit 44, and stores the time series data for each paper type. In the example of FIG. 8, the time-series data storage unit 41f stores time-series data TSD1, TSD2, TSD3,.

  Based on the discrimination result of the type discriminating unit 44, the double feed predictor detecting unit 42 detects, for each paper type, the sign of double feed or the deterioration of the separating means based on the detection result of the amount of protrusion in the type. . Specifically, for each paper type, the double feed predictor detection unit 42 determines a multiple feed predictor or a deterioration of the separation unit based on a plurality of detection results of the protruding amount of the paper type. For example, for each paper type, the double feed sign detection unit 42 determines the sign of double feed and the deterioration of the separation means based on the time series data corresponding to the paper type stored in the time series data storage unit 41f. Make a decision.

  About the point other than the above, the processing content of the double feed precursor detection part 42 may be the same as that of 1st Embodiment. However, in consideration of the difference in adsorption force and frictional resistance between sheets depending on the paper type, the double feed sign detection unit 42 uses thresholds and standards set for each paper type in sign detection and deterioration determination. Also good. In addition, when the occurrence frequency of the abnormal value (or abnormal value and abnormal value group) is higher than the reference, the double feed predictor detecting unit 42 generates the abnormal frequency (or abnormal value and abnormal value group) occurrence frequency for other paper types. Judge whether the paper is higher than the standard. If other paper types are too high, the separation means is judged to be deteriorated. If the other paper types are not high, the paper is inappropriate (for example, non-standard paper). It may be determined that That is, the double feed sign detection unit 42 may determine that the separating unit has deteriorated when the occurrence frequency of the abnormal value is higher than the reference in two or more paper types.

  The process execution unit 43 is the same as that in the first embodiment.

  FIG. 9 is a flowchart showing an example of the operation of the double feed sign detection device 40. Hereinafter, an example of the operation of the double feed sign detection device 40 will be described with reference to FIG.

  In step S <b> 21, the double feed sign detection device 40 detects the drive start of the motor that drives the pickup roll 22. The double feed sign detection device 40 is in a standby state until the start of driving is detected.

  In step S <b> 22, the double feed sign detection device 40 detects the arrival of the paper at the paper sensor 34 by the paper sensor 34.

  In step S23, the double feed sign detection device 40 carries the conveyance time from the start of paper feed to the paper sensor 34 based on the paper feed start timing detected in step S21 and the paper arrival timing detected in step S22. Is calculated.

  In step S <b> 24, the double feed sign detection device 40 acquires information indicating the paper type of the paper to be transported.

  In step S25, the double feed sign detection device 40 calculates a difference between the reference time stored in advance and the transport time calculated in step S23. In this case, a reference time corresponding to the paper type may be used.

  In step S26, the double feed sign detection device 40 accumulates the difference calculated in step S25. Specifically, the double feed sign detection device 40 updates the time-series data corresponding to the paper type determined in step S24 based on the calculated difference. Here, the number of data of the time series data is fixed to a fixed number of times, and the double feed sign detection device 40 deletes the oldest difference data when adding new difference data to the time series data. Therefore, the time-series data holds data up to the number of times going back a certain number of times from the latest data.

  In step S27, the double feed sign detection device 40 evaluates the time series data distribution (occurrence frequency) of the difference updated in step S26. Specifically, the double feed sign detection device 40 identifies a difference value (abnormal value) that exceeds a predetermined threshold among the difference values included in the time series data, and the abnormal value has occurred within a certain number of times. The number of times and the number of times the abnormal value group has occurred within a certain number of times are calculated. In this case, a threshold value corresponding to the paper type may be used.

  In step S28, the double feed sign detection device 40 determines whether or not the number of occurrences of the abnormal value calculated in step S27 exceeds a predetermined reference number, and if not (S28). : NO), the process returns to step S21, and if it exceeds (S28: YES), the process proceeds to step S29. In this case, a reference number corresponding to the paper type may be used.

  In step S29, the multifeed sign detecting device 40 determines whether or not the number of occurrences of the abnormal value group calculated in step S27 exceeds a predetermined reference number, and if not ( (S29: NO), the process returns to step S21, and if it exceeds (S29: YES), the process proceeds to step S30. In this case, a reference number corresponding to the paper type may be used.

  In step S30, the double feed sign detection device 40 determines whether or not the number of occurrences of the abnormal value and the abnormal value group exceeds the reference number for other paper types, and does not exceed the other paper types. In this case (S30: NO), the process proceeds to step S31. When other paper types are exceeded (S30: YES), the process proceeds to step S32. Here, the other paper type is, for example, one specific other paper type, another whole paper type, or any other paper type.

  In step S31, the double feed sign detection device 40 issues a warning notification about the paper. For example, a warning for prompting the user to confirm the paper is notified.

  In step S <b> 32, the double feed sign detection device 40 notifies the user and the conveyance control device 27 of a warning indicating failure of the delivery mechanism or deterioration of the separating means.

  In addition, this invention is not limited to the said embodiment, It can change variously within the range which does not deviate from the summary of this invention.

  For example, in the above embodiment, the image forming apparatus has been described as an example. However, the present invention may be applied to apparatuses other than the image forming apparatus, such as an automatic document feeder.

  DESCRIPTION OF SYMBOLS 1 Loading part, 3 discharge | emission tray, 10 image formation part, 20 conveyance apparatus, 21 delivery mechanism, 22 pick-up roll, 23 feeding roll, 24 separation roll, 25 conveyance roll, 26,34 Paper sensor, 27 conveyance control apparatus, 30 40, double feed sign detection device, 31, 41 protrusion amount detection unit, 32, 42 double feed sign detection unit, 33, 43 processing execution unit, 44 type discrimination unit, 100 image forming device, N separation unit.

Claims (5)

Sending means for separating the transported objects stacked on the stacking unit one by one and sending them in the transporting direction, wherein the transporting direction with respect to the transported object taken together with the transported target object from the stacking unit Sending means including separation means for applying a force in the reverse direction at the separation unit and separating the taken-out conveyed object from the conveyed object to be conveyed;
A protrusion amount detecting means for detecting a protrusion amount of the transported body loaded on the stacking portion in the transport direction from the stacking portion;
Based on the protrusion amount of the detection result, the double feeding sign detection means for determining a double feed sign of occurrence of the conveyance object degradation, that and not due to the deterioration of the separating means of the separating means,
I have a,
The double feed predictor detecting means has a first threshold value corresponding to an amount of protrusion to a predetermined first position beyond the separation portion as viewed from the stacking portion with respect to the amount of protrusion detected by the amount of protrusion detection means. And a second threshold value corresponding to a protruding amount up to a predetermined second position before the separating unit when viewed from the stacking unit, and the occurrence of the protruding amount exceeding the first threshold value When the frequency is higher than a predetermined reference, it is determined that the separation unit has deteriorated, and the occurrence frequency of the amount of protrusion exceeding the second threshold is higher than the predetermined reference and the first A transport apparatus characterized in that, when the occurrence frequency of the amount of protrusion exceeding the threshold is lower than a predetermined reference, it is determined that there is a sign of occurrence of double feed not caused by deterioration of the separation means .   It is a conveying apparatus of Claim 1, Comprising:
  When it is determined that the separation unit has deteriorated, the double feed predictor detection unit notifies the user of warning information regarding the deterioration of the separation unit, and a sign of occurrence of double feed not caused by the deterioration of the separation unit. If it is determined that there is an error, the user is notified of warning information regarding a sign of occurrence of double feed. It is a conveying apparatus of Claim 1 , Comprising:
A type discriminating means for discriminating the type of the transported body loaded on the stacking unit;
The double feed sign detection means detects the sign or the deterioration based on the detection result of the amount of protrusion in the type for each type of the transport object based on the determination result of the transport object type. Do,
A conveying apparatus characterized by that. Sending means for separating the transported objects stacked on the stacking unit one by one and sending them in the transporting direction, wherein the transporting direction with respect to the transported object taken together with the transported target object from the stacking unit A double feed sign connected to a transport device comprising: a separating unit that applies a force in the reverse direction at the separation unit and separates the taken-out transported object from the transported target object. A detection device,
When the transported objects loaded on the stacking unit are sent out one by one in the transporting direction by the feeding means, the amount of protrusion of the transported objects loaded on the stacking unit in the transporting direction from the stacking unit is detected. A protruding amount detecting means;
Based on the protrusion amount of the detection result, the double feeding sign detection means for determining a double feed sign of occurrence of the conveyance object degradation, that and not due to the deterioration of the separating means of the separating means,
I have a,
The double feed predictor detecting means has a first threshold value corresponding to an amount of protrusion to a predetermined first position beyond the separation portion as viewed from the stacking portion with respect to the amount of protrusion detected by the amount of protrusion detection means. And a second threshold value corresponding to a protruding amount up to a predetermined second position before the separating unit when viewed from the stacking unit, and the occurrence of the protruding amount exceeding the first threshold value When the frequency is higher than a predetermined reference, it is determined that the separation unit has deteriorated, and the occurrence frequency of the amount of protrusion exceeding the second threshold is higher than the predetermined reference and the first If the frequency of occurrence of the protrusion amount exceeding the threshold is lower than the standards set in advance, multifeed sign biopsies and judging that there is a double feed sign of occurrence of not due to degradation of the separating means Apparatus. Sending means for separating the transported objects stacked on the stacking unit one by one and sending them in the transporting direction, wherein the transporting direction with respect to the transported object taken together with the transported target object from the stacking unit To a computer connected to a transport device provided with a feeding unit including a separating unit that applies a force in the reverse direction at the separation unit and separates the taken-out conveyed object from the conveyed object to be conveyed ,
When the transported objects loaded on the stacking unit are sent out one by one in the transporting direction by the feeding means, the amount of protrusion of the transported objects loaded on the stacking unit in the transporting direction from the stacking unit is detected. To detect the amount of protrusion ,
Based on the protrusion amount of the detection result, the procedure degradation, and double feed sign of the occurrence of the conveyance object not due to degradation of the separating means, sign determining detection the separating means,
Was executed,
In the sign detection procedure, with respect to the amount of protrusion detected in the amount of protrusion detection procedure, a first threshold value corresponding to an amount of protrusion to a predetermined first position beyond the separation unit as viewed from the stacking unit; A second threshold value corresponding to a protruding amount up to a predetermined second position before the separating unit as viewed from the stacking unit, and the occurrence frequency of the protruding amount exceeding the first threshold value If it is higher than a predetermined standard, it is determined that the separation means has deteriorated, the occurrence frequency of the amount of protrusion exceeding the second threshold is higher than a predetermined standard, and the first threshold is than when the protrusion amount of frequency is lower than the standards set in advance, the multifeed sign of occurrence of not due to degradation of the separating means is a double feed sign detection, characterized in that determining Program.

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